1. Field of the Invention
The present invention relates to networking and, more specifically, to implementing an interface bundle in a virtual network device.
2. Description of the Related Art
In order to provide increased network reliability, redundant switches and links are often included in a network. If a switch or link fails, a redundant switch or link, already in place within the network, can quickly be enabled to replace the failed switch or link. Since the redundant switch or link can typically be enabled as a replacement more quickly than the failed component can be replaced or repaired, having redundant links and/or switching can provide a more reliable network.
When redundant components are included within a network, it is often desirable to be able to use the redundant components during normal network operation, before the failure of corresponding components. For example, if two links are implemented between a pair of switches, it is desirable to use both links (as opposed to leaving one link idle) to provide increased bandwidth. However, if multiple redundant links are active at the same time, management of those links may be undesirably complicated (e.g., due to the need to avoid bridging loops).
One way to avoid the complexity of having several independent redundant links is to operate those links as single logical transmission path, such as that provided using a link bundling technique like EtherChannel™ or link aggregation (defined in IEEE 802.3). For example, an EtherChannel™ port bundle can be formed from several ports on a switch, each of which is coupled to a respective link in a group of links coupling that switch to another switch. Once an EtherChannel™ port bundle is formed, the port bundle can be managed as a single bridge port by routing protocols such as spanning tree, thus simplifying management of the redundant links.
Currently, there are situations in which link bundling techniques cannot be used. For example, currently all of the ports in an EtherChannel™ port bundle must be included in the same network device. It is desirable to extend the situations in which port bundles can be used.